In Part C of Lab 8, you will prepare a phosphate buffer of a certain pH using the direct method. The questions below are to give you practice carrying out the necessary calculation for preparing the buffer from the correct phosphate compound. When you next come to lab to complete Part C of Lab 8, you will need to carry out this calculation again based on the actual mass of Na₂HPO4 7 H₂O that you weigh out. (a) Select a pH for your buffer solution. (Please make sure you and your lab partner(s) select the same pH, or someone will need to redo their calculations in lab.) --Select- (b) Based on the pH selected, will you need to use Na3PO4 12 H₂O or NaH2PO4 H₂O in order to generate a buffer of the desired pH? 2- 3- Hint: To answer this, you will need to determine pK values corresponding to the mixtures of the HPO anion with both phosphate anions PO4 and H2PO4 and evaluate which of these mixtures is closer to your target pH value. Na3PO4 12 H₂O NaH2PO4 H₂O • (c) Assuming you use exactly 3.000 g Na₂HPO4 7 H2O to make your buffer solution, what mass of the other phosphate compound will you need to add in order to generate the desired pH? Hint: You will need to use the Henderson-Hasselbalch Equation for this calculation. Pay attention to the correct molar masses for the phosphate compounds, as well (including the H₂O molecules!). (Enter your answer to the closest 0.001 g.) g

Consider a buffer solution that is 0.47 M HCN and 0.47 M NaCN. (Ka(HCN) = 4.9 × 10−10) Calculate the pH of the solution after the addition of 0.20 mol of NaOH to 1.00 L of the buffer solution. Assume no volume change upon addition of NaOH to the buffer. 4 sig figs please

In a qualitative analysis procedure, a chemist adds HCl to an unknown group of ions and then saturates the solution with H2S so that the solution is 0.3 M in HCl and 0.10 M in H2S. (a) What is the [HS -] of the solution?

Can someone help me with this problem? (in handwritten form)

You are titrating 20.0mL sample of 0.131 M Ba(OH)2 with 0.350 M HCL.  (a) What volume in mL of HCL solution is needed to reach the equivalence point? (b) What is the pH after 20.0ml of HCL have been added. (c) Sketch a titration curve for the above process. Label the axes and the points calculated in (a) and (b) above.

A solution is prepared that is initially 0.087 M in benzoic acid (HC6H5CO2) and 0.11 M in potassium benzoate (KC6H5CO2). Complete the reaction table below, so that you could use it to calculate the pH of this solution. User to stand for the unknown change in [H3O+] You can leave out the M symbol for molarity

The final volume of buffer solution must be 100.00 mL and the final concentration of the weak acid must be 0.100 M. Based on this information, what mass of solid conjugate base should the student weigh out to make the buffer solution with a pH of 3.50? mass= Based on this information, what volume of acid should the student measure to make the buffer solution? volume = g ml.

Can you please show all steps

Calculate the pH of a buffer solution prepared by dissolving 0,48 mole of sodium fluoride (NaF) and 1.0 mole of hydrofluoric acid (HF) in enough water to make 1.0 liter of solution. [K(HF) = 6,8 x 1o-j Your answer should have 2 sig figs

Given that Ka’s for hydrofluoric acid (HF) and boric acid (H3BO3) are 6.3 × 10^–4and 5.4 × 10^–10, respectively, calculate the pH of the following solutions: (a)The mixture from adding 50 mL 0.2 M HF to 50 mL 0.5 M sodium borate (NaH2BO3).  (b)The mixture from adding an additional 150 mL 0.2 M HF to the solution in (a), i.e., a total of 200 mL 0.2 M HF was added to 50 mL 0.5 M NaH2BO3.